Across
- 3. Eco-friendly energy descriptor
- 5. Converts wind to electricity
- 8. Sustainable energy type
- 9. Ocean energy type
- 10. A biofuel source
- 13. Long-term viable energy
- 15. Energy from the sun
Down
- 1. Heat from beneath the Earth's surface
- 2. Energy from flowing water
- 4. Energy from organic materials
- 6. Biofuel from crops
- 7. Pollution-free energy
- 11. Turbine-powered energy source
- 12. Solar device component
- 14. Energy from ocean waves